U.S. patent number 6,059,025 [Application Number 09/035,374] was granted by the patent office on 2000-05-09 for heat exchanger configuration.
This patent grant is currently assigned to Monsanto Enviro-Chem Systems, Inc.. Invention is credited to Lawrence M. Hossfeld.
United States Patent |
6,059,025 |
Hossfeld |
May 9, 2000 |
Heat exchanger configuration
Abstract
A plate-type heat exchanger configuration which facilitates
fluid flow along a generally "L" or "S" shaped path and which
includes a plurality of heat exchanger plates with at least one of
the edges comprised of a pair of edge sections which terminate in
different edge configurations. The invention also relates to a
plate configuration for such a heat exchanger.
Inventors: |
Hossfeld; Lawrence M.
(Minnetonka, MN) |
Assignee: |
Monsanto Enviro-Chem Systems,
Inc. (St. Louis, MO)
|
Family
ID: |
21882293 |
Appl.
No.: |
09/035,374 |
Filed: |
March 5, 1998 |
Current U.S.
Class: |
165/166; 165/76;
165/82; 165/81 |
Current CPC
Class: |
F28D
9/0068 (20130101); F28F 9/001 (20130101); F28F
2250/108 (20130101) |
Current International
Class: |
F28F
9/00 (20060101); F28D 9/00 (20060101); F28F
003/06 () |
Field of
Search: |
;165/166,82,81,76 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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580039 |
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Jul 1925 |
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FR |
|
0020997 |
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Feb 1981 |
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JP |
|
0071795 |
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Jun 1981 |
|
JP |
|
0202096 |
|
Sep 1986 |
|
JP |
|
0205795 |
|
Sep 1986 |
|
JP |
|
2063450 |
|
Jun 1981 |
|
GB |
|
Primary Examiner: Atkinson; Christopher
Attorney, Agent or Firm: Senniger, Powers, Leavitt &
Roedel
Parent Case Text
This application claims the benefit of Provisional Application
Serial No. 60/039,951 filed Mar. 6, 1997.
Claims
What is claimed is:
1. A plate-type heat exchanger for heat exchange between first and
second fluid streams, said heat exchanger comprising:
a stack of generally rectangular heat exchanger plates comprised of
a first set of said heat exchanger plates and a second set of said
heat exchanger plates interleaved between said first set so that
said stack is comprised of alternating heat exchanger plates from
said first and second sets, each of said plates having a first
fluid surface and an opposite second fluid surface and positioned
in spaced, generally parallel relationship to one another so that
the first fluid surface of plates in said first set faces the first
fluid surface of plates in said second set and the second fluid
surface of plates in said first set faces the second fluid surface
of plates in said second set, each of said plates further having a
pair of generally parallel first edges and a pair of generally
parallel second edges, said second edges being generally
perpendicular to said first edges, at least one of said first and
second edges having first and second edge sections, each of said
first and second edges and each of said first and second edge
sections terminating in either a first edge configuration or a
second edge configuration with said first edge section terminating
in one of said first and second edge configurations and said second
edge section terminating in the other of said first and second edge
configurations, and further with each of said first and second
edges and said first and second edge sections of said first set of
plates terminating in one of said first and second edge
configurations and each of the corresponding first and second edges
and first and second edge sections of said second set of plates
terminating in the other of said first and second edge
configurations, said stack being mounted within a frame comprising
first and second end frame members, a plurality of corner posts
extending between said first and second end frame members and a
mid-post extending between said first and second end frame members
and positioned between two adjacent corner posts;
a first set of fluid flow directing members positioned between the
first fluid surface of each heat exchanger plate in said first set
and the first fluid surface of an adjacent heat exchanger plate in
said second set; and
a second set of fluid flow directing members positioned between the
second fluid surface of each heat exchanger plate in said first set
and the second fluid surface of an adjacent heat exchanger plate in
said second set.
2. The heat exchanger of claim 1 wherein said mid-post separates
said first and second edge sections.
3. The heat exchanger of claim 1 wherein one of said first edges
includes first and second edge sections with said first edge
section of said one first edge being adjacent to one of said second
edges and said second edge section of said one first edge being
adjacent to the other of said second edges.
4. The heat exchanger of claim 3 wherein said first set of flow
directing members extends from said first edge section of said one
first edge to said other of said second edges.
5. The heat exchanger of claim 4 wherein said second set of flow
directing members extends from said second edge section of said one
first edge to said one of said second edges.
6. The heat exchanger of claim 3 wherein the other of said first
edges includes first and second edge sections with said first edge
section of said other first edge being adjacent to said one of said
second edges and said second edge section of said other first edge
being adjacent to said other of said second edges.
7. The heat exchanger of claim 6 wherein said first set of flow
directing members extends from said first edge section of said one
first edge to said second edge section of said other first
edge.
8. The heat exchanger of claim 7 wherein said second set of flow
directing members extends from said second edge section of said one
first edge to said first edge section of said other first edge.
9. The heat exchanger of claim 6 wherein said first set of flow
directing members extends from said first edge section of said one
first edge to said other of said second edges and wherein said
second set of flow directing members extends from said second edge
section of said other first edge to said one of said second
edges.
10. The heat exchanger of claim 1 wherein one of said first and
second edge configurations is an offset configuration and the other
of said first and second edge configurations is an offset receiving
configuration.
11. The heat exchanger of claim 10 including spring assemblies
positioned between adjacent plates along said first and second
edges.
12. A heat exchanger plate for a plate-type heat exchanger for heat
exchange between first and second fluid streams, said plate
comprising:
first and second generally rectangular planar surfaces on opposite
sides of said plate;
a pair of generally parallel first edges;
a pair of generally parallel second edges, said second edges being
generally perpendicular to said first edges and at least one of
said first and second edges having first and second edge
sections;
a mid-post notch separating said first and second edge
sections;
each of said first and second edges and each of said first and
second edge sections terminating in either a first edge
configuration or a second edge configuration with said first edge
section terminating in one of said first and second configurations
and said second edge section terminating in the other of said first
and second edge configurations.
13. The heat exchanger plate of claim 12 wherein one of said first
edges includes first and second edge sections.
14. The heat exchanger plate of claim 13 wherein the other of said
first edges includes first and second edge sections.
15. The heat exchanger of claim 14 wherein said first edge section
of said one first edge and said first edge section of said other
first edge are adjacent to one of said second edges and said second
edge section of said one first edge and said second edge section of
said other first edge are adjacent to the other of said second
edges.
16. The heat exchanger of claim 15 wherein said second edge section
of said one first edge and said first edge section of said other
first edge terminate in said first edge configuration and wherein
said second edge section of said other first edge and said first
edge section of said one first edge terminate in said second edge
configuration.
17. The heat exchanger of claim 16 wherein said one second edge
terminates in said first edge configuration and said other second
edge terminates in said second edge configuration.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a plate type, non-welded
heat exchanger configuration and more particularly to a plate type,
non-welded heat exchanger configuration which facilitates fluid
flow through the heat exchanger along a generally "L" shaped path
from one face to a face disposed at right angles thereto or
facilitates the entry or exit of both fluids on the same face or on
opposing parallel faces. The invention also relates to a heat
exchanger plate configuration for use in the above heat
exchanger.
2. Description of the Prior Art
Various types of heat exchangers currently exist for transferring
heat from one fluid stream to another. Although it is contemplated
that the concepts employed in the present invention may be useful
in heat exchangers in which at least one of the fluids is a liquid,
the primary application of the present invention and the
application which is described in the preferred embodiment is an
application where both of the fluids are gasses. A common type of
heat exchanger is a plate type, non-welded heat exchanger of the
type disclosed in U.S. Pat. No. 4,442,886 issued to Dinulescu. The
entire disclosure of this U.S. Pat. No. 4,442,886 is incorporated
herein by reference.
In general, a plate type, non-welded heat exchanger comprises a
plurality or stack of parallel heat exchanger plates. These plates
are spaced from one another to define alternate flow channels for
two fluids of different temperatures. The plate type heat exchanger
as disclosed in U.S. Pat. No. 4,442,886 embodies a generally
rectangular configuration referred to as a plate block. The block
comprises a stack of generally rectangular plates which are
assembled and maintained in parallel relationship relative to one
another by a rigid frame assembly. The frame assembly includes
corner posts positioned at the corners of the rectangular plates
and at right angles to each plate. A pair of connecting end walls
join the corner posts and are disposed in parallel relationship
relative to the plates. The heat exchanger block configuration of
U.S. Pat. No. 4,442,886 defines a pair of opposing first
inlet/outlet faces which are parallel to one another and
perpendicular to the plates and a pair of opposing second
inlet/outlet faces which are parallel to one another, perpendicular
to the plates and perpendicular to the pair of opposing first
inlet/outlet faces.
The plate blocks of U.S. Pat. No. 4,442,886 can be used separately
or can be combined with other blocks to form various configurations
of heat exchanger assemblies. The possible configurations can be
further increased through the use of additional ductwork and/or a
flow manifolds. The possible configurations that can be formed with
the blocks of U.S. Pat. No. 4,442,886, however, are limited. For
example, in the block of the '886 patent, one of the fluids can
enter one of the faces and exit from the same face or from an
opposing parallel face, but cannot enter a face and exit from a
face which is perpendicular to the entering face. Further, in the
block of the '886 patent, the two fluids must enter on different
faces. This necessarily limits the configurations which are
possible.
Accordingly, there is a need in the art for a heat exchanger unit
or block which is capable of overcoming this deficiency, thereby
significantly increasing the configurations of heat exchanger
assemblies that can be formed.
SUMMARY OF THE INVENTION
In contrast to the prior art, the present invention relates to a
plate type, non-welded heat exchanger unit in which both fluids can
enter or exit on the same face or an opposing parallel face or the
same fluid can enter through one face and exit from a second face
at right angles to the entering face. The invention also relates to
a heat exchanger plate configuration for use in the above heat
exchanger. The ability of the heat exchanger of the present
invention to function as described above significantly increases
the possible heat exchanger assembly configurations which can be
formed.
More specifically, the heat exchanger of the present invention
includes a plurality or stack of generally rectangular heat
exchanger plates. These plates are positioned in parallel
relationship relative to one another and are maintained as a unit
in such relationship by a rigid frame assembly. The frame assembly
includes a plurality of corner posts positioned at the corners of
the plates and at right angles to each plate. The frame assembly
further includes a pair of end plates or end frame members which
inter-connect the corner posts and which extend generally parallel
to the plates.
The stack of plates forming the heat exchanger unit or block
includes a pair of opposing first inlet/outlet faces which are
parallel to one another and perpendicular to the plates and a pair
of opposing second inlet/outlet faces which are parallel to one
another, perpendicular to the plates and also perpendicular to the
pair of first inlet/outlet faces.
Each plate includes a generally rectangular configuration having a
pair of opposing first edges which are parallel to one another and
a pair of
opposing second edges which are parallel to one another and
perpendicular to the pair of first opposing edges. The pair of
opposing first edges and the pair of opposing second edges
intersect with one another to define corners of the plate.
Each of the first and second opposing edges includes either a first
edge configuration in the form an offset edge or of a second edge
configuration in the form of an offset receiving edge, with at
least one of the first and second opposing edges having both an
offset edge section and an offset receiving edge section. In the
embodiment of the present invention, an offset edge or an offset
edge section is designed to receive a spring assembly and define a
face or a face section through which one of the fluids can enter or
exit the heat exchanger unit. Preferably at least two of the first
and second opposing edges will have both an offset edge section and
an offset receiving edge section.
Each of the first and second opposing edges which includes both an
offset edge section and an offset receiving edge section further
includes a transition area between the offset edge section and the
offset receiving edge section and a mid-post assembly positioned in
the transition area. The mid-post assembly includes a mid-post
extending parallel to the corner posts and perpendicular to the
plates which interfaces with the plates to seal the flow passages
in adjacent plates from one another. Each plate is further provided
with a plurality of flow channel ribs for directing the flow of its
respective fluid from the inlet face or face section to the outlet
face or face section.
Accordingly, it is an object of the present invention to provide a
plate type, non-welded heat exchanger which significantly increases
the possible heat exchanger assembly configurations.
Another object of the present invention is to provide a plate type,
non-welded heat exchanger in which both fluids can enter or exit
along the same inlet/outlet face or along opposing, parallel
inlet/outlet faces.
Another object of the present invention is to provide a plate type,
non-welded heat exchanger in which the same fluid can enter through
a first inlet/outlet face and exit through a second inlet/outlet
face which is at right angles relative to the entry face.
A further object of the present invention is to provide a heat
exchanger assembly embodying a plurality of heat exchanger units in
which at least one such unit is of the type described above.
A still further object of the present invention is to provide a
heat exchanger plate having a configuration for use in the above
heat exchanger unit.
These and other objects of the present invention will become
apparent with reference to the attached drawings and to the
description of the preferred embodiment.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a single heat exchanger block or
unit in accordance with the present invention with portions shown
in broken lines.
FIG. 2 is an exploded, isometric view of a plurality of heat
exchanger plates and air and flue gas ribs for a portion of the
heat exchanger block or unit in accordance with the present
invention.
FIG. 3 is an elevational view of one of the heat exchanger plates
and air flow ribs in the stack of FIG. 1, with the end cover and
several plates removed.
FIG. 4 is an elevational view, similar to that of FIG. 3, of a
second heat exchanger plate and flue gas flow ribs.
FIG. 5 is a sectional view of a heat exchanger unit of the present
invention, with portions removed, as viewed along the section line
5--5 of FIGS. 3 and 4.
FIG. 6 is a sectional view, with portions removed and showing a
representation flue gas flow rib, of a portion of a heat exchanger
unit of the present invention as viewed along the section line 6--6
of FIGS. 3 and 4.
FIG. 7 is a sectional view, with portions removed and showing a
representative air flow rib, of a portion of a heat exchanger unit
of the present invention as viewed along the section line 7--7 of
FIGS. 3 and 4.
FIG. 8 is an elevational side view of the spring assembly.
FIG. 9 is an elevational end view of the spring assembly.
FIG. 10 is a sectional view through the ends of adjacent heat
exchanger plates showing an offset edge configuration and a
corresponding turn-up or offset receiving edge configuration.
FIG. 11 is a top elevational view, partially in section and with
portions removed, showing one embodiment of a corner post
assembly.
FIG. 12 is a top elevational view, partially in section and with
portions removed, showing an alternate embodiment of a corner post
assembly.
FIG. 13 is a top elevational view, partially in section and with
portions removed, showing the mid-post assembly.
FIG. 14 is an isometric, exploded view, similar to that of FIG. 2,
showing a further embodiment of a heat exchanger unit in accordance
with the present invention.
FIG. 15 is an isometric, exploded view, similar to that of FIGS. 2
and 14, showing a still further embodiment of a heat exchanger unit
in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention relates generally to a plate type, non-welded
heat exchanger comprising a plurality of parallel plates. Heat
exchangers of this type are designed for transferring heat from a
first fluid to a second fluid. Usually, these fluids are gasses. A
common application for heat exchangers of this type is to transfer
heat from flue gas to ambient air for the purpose of preheating the
air for subsequent use. Accordingly, throughout the description of
the preferred embodiment, the fluid streams shall be referred to as
first and second fluid streams or simply as "flue gas" or
"air".
With reference first to FIG. 1, the heat exchanger 10 of the
present invention, sometimes also referred to herein as a heat
exchanger unit or heat exchanger block, includes a plurality of
generally rectangular plates 11. These plates are generally
parallel to one another and extend throughout the entire
rectangular configuration of the unit 10. The spaced plates 11
define alternate flow channels for flue gas and for air.
The plurality or stack of heat exchanger plates 11 is assembled and
maintained in a unit as shown by a rigid frame assembly comprising
a plurality of corner posts 12(a-d) and a pair of end plates 14 and
15. In the preferred embodiment, one of the corner posts 12(a-d) is
positioned at each corner of each of the rectangular plates 11.
Each of the corner posts 12(a-d) extends parallel to one another
and perpendicular to each of the plates 11. The corner posts
12(a-d) are connected with and retained by the end plates 14 and
15. The end plates 14 and 15, as shown, are generally parallel to
the plates 11. Although the end plates 14 and 15 in the preferred
embodiment are shown as being solid rectangular plates, they can,
if desired, comprise frame members or other similar supporting
structure.
When assembled as shown in FIG. 1, the heat exchanger block or unit
10 defines a pair of opposing first inlet/outlet faces 18 and 19
which are parallel to one another and are perpendicular to the
plates 11. The inlet/outlet face 18 extends between the corner
posts 12b and 12c and includes face sections 18a and 18b. The
inlet/outlet face 19 extends between the corner posts 12a and 12d
and includes face sections 19a and 19b. The unit 10 also includes a
pair of opposing second inlet/outlet faces 20 and 21. These faces
20 and 21 are parallel to one another, are perpendicular to the
plates 11 and are perpendicular to the pair of opposing first
inlet/outlet faces 18 and 19. The inlet/outlet face 20 extends
between the corner posts 12a and 12b, while the inlet/outlet face
21 extends between the corner posts 12c and 12d.
Positioned between the corner post 12b and 12c in the embodiment of
FIG. 1 is a mid-post assembly 22a which separates face section 18a
from face section 18b. A similar mid-post assembly 22b is
positioned between the corner posts 12a and 12d to separate face
section 19a from face section 19b. These mid-post assemblies 22a
and 22b are positioned in a transition area between heat exchanger
plate sections and function to stabilize the plates 11 and to seal
alternating flow chambers within the plates from one another.
In the embodiment of FIG. 1, flue gas enters the unit 10 through
the inlet/outlet face section 18b between the mid-post 22a and the
corner post 12c and exits through the inlet/outlet face 20 which is
perpendicular to the face section 18b. The air enters the unit 10
through the inlet/outlet face section 18a between the corner post
12b and the mid-post 22a and exits through the inlet/outlet face 21
which is perpendicular to the face section 18a.
Reference is next made to FIGS. 2, 3, and 4 which show various
views of the heat exchanger plates and flow ribs used in the unit
of FIG. 1. As shown best in FIG. 2, the stack of plates 11 comprise
alternating air plates 24 and flue plates 25 which together define
alternating air flow and flue gas flow chambers. Thus, the stack
comprises a first set of heat exchanger plates in the form of the
plates 24 and a second set of heat exchanger plates 25 interleaved
between the first set. In the preferred embodiment, the air plates
24 are those plates which define the upper surface of an air flow
chamber while the flue plates 25 are those plates which define the
upper surface of a flue gas flow chamber.
Each of the air plates 24 has a generally rectangular configuration
with a pair of generally planar first and second or top and bottom
surfaces, a pair of first opposing, parallel edges 26 and 27 and a
pair of second opposing, parallel edges 28 and 29 which are
perpendicular to the first opposing edges 26 and 27. Each of the
edges 28 and 29 comprise edge sections 28a, 28b and 29a, 29b,
respectively. Each of the edges 26, 27, 28 and 29, or a portion
thereof, terminates in either a first edge configuration in the
form of an offset edge configuration 34 or a second edge
configuration in the form of a turn-up or offset receiving edge
configuration 35 as shown in FIG. 10. In FIG. 10, the offset edge
configuration 34 comprises an offset leg section 36 perpendicular
to the main plate surface 24/25 and a laterally extending leg
section 38 at right angles to the leg 36. The turn-up or offset
receiving edge configuration 35 includes a leg section 39 which is
an integral extension of the main plate surface 24/25 and an
up-turned leg section 40 positioned at the end of the leg 39 and at
right angles thereto. As shown in FIGS. 5, 6 and 7, and as will be
described in greater detail below, the combination of the offset
edge 34 configuration and the offset receiving edge 35
configuration provide opposite surfaces for engagement with the
spring assembly shown in FIGS. 8 and 9.
In the embodiment of FIG. 2, the edge 26 and the edge sections 28b
and 29b are provided with offset edge configurations, while the
edge 27 and the edge sections 28a and 29a are provided with offset
receiving edge configurations. Each of the edges 28 and 29 includes
a transition area 42 in the form of a recess positioned between the
edge sections 28a and 28b and between the edge sections 29a and
29b, respectively. Each of the plates 24 is also provided with a
corner 44 positioned at the intersections of the edges 26 and 27
with the edges 28 and 29. In the preferred embodiment, these
corners 44 are notched.
Similarly, each of the flue plates 25 includes a pair of first
opposing, parallel edges 30 and 31 and a pair of second opposing,
parallel edges 32 and 33 which are perpendicular to the first
opposing edges 30 and 31. Each of the edges 32 and 33 is likewise
comprised of edge sections 32a, 32b and 33a, 33b, respectively.
Further, similar to the plates 24, each edge and edge section of
the flue plate 25 terminates in either an offset edge configuration
34 or an offset receiving edge configuration 35 as shown in FIG.
10. In the preferred embodiment, the edge 31 and the edge sections
32a and 33a are provided with offset edge configurations 34, while
the edge 30 and the edge sections 32b and 33b are provided with
offset receiving edge configurations 35. Also similar to the plates
24, each plate 25 is provided with a pair of transition areas 42
positioned between the edge sections 32a and 32b and between the
edge sections 33a and 33b. Each plate 25 is also provided with a
corner 44 at the intersections of the edges 30 and 31 with the
edges 32 and 33.
In the preferred embodiment, the transition areas 42 are positioned
mi-way between the edges 26 and 27 of the air plate 24 and midway
between the edges 30 and 31 of the flue gas plate 25. Thus, in the
preferred embodiment, both plates 24 and 25 are identical in
structure; however, each plate 25 has an orientation relative to
each plate 24 which is rotated 180.degree. about an axis
perpendicular to the surface of the plates.
When the plates 24 and 25 are assembled into the unit 10 of FIG. 1,
the edges 26 and 30 correspond to the inlet/outlet face 20 and the
edges 27 and 31 correspond to the inlet/outlet face 21. Similarly,
the edge sections 29a and 33a correspond to the inlet/outlet face
section 18a, the edge sections 28a and 32a correspond to the
inlet/outlet face section 19a, the edge sections 29b and 33b
correspond to the inlet/outlet face section 18b and the edge
sections 28b and 32b correspond to the inlet/outlet face section
19b.
Positioned between the lower surface of each air plate 24 and the
upper surface of each flue gas plate 25 as shown in FIG. 2 is an
air flow rib assembly 45 and a plurality of spring assemblies 46.
Similarly, positioned between the lower surface of each flue gas
plate 25 and the upper surface of each air plate 24 is a flue gas
flow rib assembly 48 and a plurality of spring assemblies 46.
As best shown in FIG. 3, the air flow rib assembly includes a
plurality of ribs 45a, 45b, 45c, etc. which extend from the edge
section 33a to the edge 31. Each of the air flow ribs 45a-c, etc.
includes connection means at their ends for inter-connection with
the spring assemblies 46 (FIG. 2) in a manner known in the art.
Accordingly, in the preferred embodiment, the air enters the heat
exchanger unit along the edge section 33a (corresponding to the
inlet/outlet face section 18a of FIG. 1) and follows the path of
the air flow ribs 45a-c, etc. and exits from the unit along the
edge 31 (corresponding to the inlet/outlet face 21 of FIG. 1). The
top surface of the plate 25 is provided with a plurality of dimples
49 for stabilizing and providing proper spacing for the ribs 45a-c,
etc.
As best shown in FIG. 4, each flue gas flow rib assembly 48
includes a plurality of flue gas flow ribs 48a, 48b, 48c, etc.
which extend from the edge section 29b of plate 24 to the edge 26.
Similar to the rib assembly 46, the plurality of ribs 48a-c, etc.
are provided with connection means at their ends for connecting the
ribs to the spring assemblies 46 in a manner known in the art. A
plurality of dimples 49 are also provided on the surface of the
plates 24 to stabilize and provide proper spacing for the ribs
48a-c, etc. Accordingly, in the preferred embodiment, the flue gas
enters the heat exchanger unit along the edge section 29b
(corresponding to the inlet/outlet face section 18b of FIG. 1) and
follows the path of the flue gas flow ribs 48a-c, etc. and exits
from the unit along the edge 26 (corresponding to the inlet/outlet
face 20 of FIG. 1).
The spring assemblies 46 have a structure known in the art and are
shown best in FIGS. 8 and 9. Each spring assembly includes a
generally U shaped base portion 50 constructed of metal or other
rigid material, a compressible, resilient member 52 usually
constructed of a synthetic material and a relatively rigid spacer
element 51. As is known in the art, the rigid spacer element 51
forms loop sections 53 as shown in FIG. 8 which define open
portions for passage of air or flue gas. These loop sections 53
also provide connection openings for connection of the flow ribs
45a-c, etc. and 48a-c, etc in a manner known in the art.
FIGS. 5, 6 and 7 comprise various cross-sectional configurations of
a plurality of plates and associated structure as viewed along the
section lines 5--5, 6--6 and 7--7 of FIGS. 3 and 4. As shown in
FIG. 5, the air flow passages are open at the inlet/outlet face 21
but closed at the inlet/outlet face 20, while the flue gas flow
passages are open to the inlet/outlet face 20 and closed at the
inlet/outlet face 21. In FIG. 6 the
air flow passages are open and the flue gas flow passages are
closed at both the inlet/outlet face section 19a and the
inlet/outlet face section 18a. In FIG. 7, the air flow passages are
closed and the flue gas flow passages are open at both the
inlet/outlet face section 19b and the inlet/outlet face section
18b.
FIGS. 11 and 12 disclose various corner post assemblies 12
positioned at each corner of the plurality of plates for
stabilizing the plates and for sealing the plates at their corners
to prevent or minimize leakage between the flue gas flow passages
and the air flow passages. The corner assembly 12 of FIG. 11 is
designed for use with a plurality of plates which are notched to
create uniform interior square corners, while the corner post
assembly 12 of FIG. 12 is designed for use with plates having a
shallower notch along the offset receiving edge to create uniform
exterior square corners. In the embodiment of FIG. 11, the corner
post assembly 12 includes a plurality of rigid angle members 54, a
pair of spring members in the form of a tubular configuration of
spring metal or the like, a rigid angle member 56 and an angle
shaped piece of compression material 57 engaging the edges of the
plates. The angle members 54 are in turn retained by the top and
bottom end plates 14 and 15 (FIG. 1) or by other portions of the
housing in a manner known in the art. The spring members 55,55
exert a force against the rigid angle member 56 and thus the
compression member 57, thereby forming a seal between adjacent
plates. If desired, caulking (identified as the cross-hatched
material) or other material can be introduced between the plates in
the area of the corner to further seal any leaks that may occur.
The corner post assembly of FIG. 11 can be used with any of the
embodiments of FIGS. 2, 14 and 15, but must be used with the
embodiment of FIG. 14.
The corner post assembly 12 of FIG. 12 is similar in that it
includes a plurality of rigid angle members 58, a plurality of
spring members 59 form of rolled up spring metal, a rigid angle
member 60 and a compression member 61 engaging the edges of each of
the plates. The angle members are connected with the end plates 14
and 15 or other portions of the frame or housing in a manner which
causes a force to be exerted through the spring members 59 against
the angle member 60 and thus the compression member 61, thereby
sealing the chambers between adjacent plates from one another. The
corner post assembly of FIG. 12 can be used with the embodiments of
FIGS. 2 and 15, but is preferably not used with the embodiment of
FIG. 14.
Reference is next made to FIG. 13 illustrating the mid-post
assembly 22. The mid-post assembly is designed to stabilize the
plates at the transition area 42 and to form a seal between
adjacent chambers in the plates in this transition area. The
mid-post assembly includes a plurality of rigid angle members 62,
63 and 64, a pair of elongated tubular spring members 65,65 a U
shaped rigid member 66 and a U shaped compression member 68 adapted
for engagement with the edges of the plates in the transition area.
When assembled, the rigid angle members 62, 63, and 64 are
connected with the end plates 14 and 15 (FIG. 1) or with other
frame or housing portions of the unit. A force is exerted against
the rigid member 66 by the spring members 65,65, thereby pressing
the compression member 68 against the edges of the plates in the
transition area. This seals the respective flow chambers and
prevents leakage from one chamber to an adjacent chamber. To
further seal this area, caulking 69 can be introduced between the
plates in the transition area and adjacent to the compression
member 68. Preferably, the caulking material 69 is retained by a
caulk retaining rib 70 positioned between the plates and stabilized
and connected at one end by the connection hook 71 to a portion of
the spring assembly 46.
FIGS. 14 and 15 are views similar to that of FIG. 2 except that
they illustrate alternate embodiments of heat exchanger
configurations in accordance with present invention. In the
embodiment of FIG. 14, the air inlet and the flue gas inlet are
along the same edge and the air outlet and the flue gas outlet are
along the same edge. In this embodiment, the edge 27 and the edge
sections 28b and 29a of the plate 24 are provided with offset edge
configurations and the edge 26 and the edge sections 28a and 29b
are provided with offset receiving edge configurations. The edge 30
and edge sections 32a and 33b of the plate 25 in this embodiment
are provided with offset edge configurations, while the edge 31 and
the edge sections 32b and 33a are provided with offset receiving
edge configurations.
FIG. 15 shows a plate structure similar to the plate structure of
FIG. 2, but with an air flow rib assembly 45 and a flue gas flow
rib assembly 48 causing the air and flue gas to enter along
opposing, parallel edges instead of along the same edge as in the
embodiment of FIG. 2.
Accordingly, with the heat exchanger in accordance with the present
invention, both air and flue gas can enter or exit on the same
inlet/outlet face as shown in the embodiments of FIGS. 1-7 and FIG.
14 or on opposing but parallel inlet/outlet faces as shown in FIG.
15. The heat exchanger of the present invention also facilitates
entry of the same fluid, whether it be air or flue gas, through a
first inlet/outlet face and exit through a second inlet/outlet face
which is at right angle to the entering face in a generally "L"
shaped path as shown in FIGS. 1-7 and FIG. 15.
The structure which enables this air and flue gas passage includes
a plurality of heat exchanger plates, with each plate being
generally rectangular in configuration and having a pair of
opposing, parallel first edges and a pair of opposing, parallel
second edges which are perpendicular to the opposing first edges.
At least one of these first and second edges includes first and
second edge sections. Each of the opposing first and second edges
terminates in either an offset edge configuration or an offset
receiving edge configuration, with at least one of the opposing
first and second edges (the one including first and second edge
sections) having both an offset edge configuration section and an
offset receiving edge configuration section. In the preferred
embodiment, two opposing edges have first and second edge sections
and thus both an offset edge configuration section and an offset
receiving edge configuration section. Each of those opposing edges
includes a transition area separating the offset edge configuration
section from the offset receiving edge configuration section. When
assembled, a mid-post assembly is provided in the transition area
to stabilize and seal the plates at that point. Although not a
necessity, it is preferable for the transition area to be
equidistant between the ends of an edge to allow the same plate to
be used both as an air plate and as a flue gas plate.
Although the description of the preferred embodiment has been quite
specific, it is contemplated that various modifications could be
made to the preferred and alternate embodiments without deviating
from the spirit of the present invention. Accordingly, it is
intended that the scope of the present invention be dictated by the
appended claims rather than by the description of the preferred
embodiment.
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